CITY OF SAN MATEO
CITY OF SAN MATEO
Agenda Report
City Hall
330 W. 20th Avenue
San Mateo CA 94403
www.cityofsanmateo.org
Agenda Number: 8 Section Name: CONSENT CALENDAR Account Number: 72-4674 File ID: 25-10298 TO: City Council
FROM: Alex Khojikian, City Manager
PREPARED BY: Public Works Department
MEETING DATE: September 02, 2025
SUBJECT:
Basins 2 and 3, Underground Flow Equalization System (UFES) Construction — Contract Contingency Increase RECOMMENDATION:
Approve an increase to the contingency reserve to the construction contract with Anderson Pacific Engineering Construction, Inc. for the Underground Flow Equalization System project in the amount of $600,000, for a new total revised contingency amount of $6,271,000; and authorize the Public Works Director to execute contract change orders within the contingency amount.
BACKGROUND:
The Clean Water Program (CWP) includes various projects to improve the City’s sanitary sewer system to improve flow management and increase capacity to prevent sanitary sewer overflows. Included in the Basins 2 and 3 project is the Underground Flow Equalization System (UFES) Project, which consisted of constructing an underground storage tank of five million gallons and collection system improvements.
On June 7, 2020, City Council awarded a construction contract to Anderson Pacific Engineering Construction Inc. (APEC) for construction of the UFES Project (Project) in the amount of $55,277,330 and approved a contingency reserve of $4,500,000. The contingency reserve was established to address and mitigate potential unknowns that may arise during construction and was approximately 8 percent of the agreement’s value.
On August 16, 2021, City Council approved Contract Change Order No. 4 to the contract in the amount of $3,877,875 adding construction of approximately 745 linear feet of new 30-inch sewer on Delaware Street between 25th and 28th Avenues to connect the southern end of the original scope to the northern end of the Delaware Relief Sewer construction package. At that time, Council also approved an increase to the contingency reserve in the amount of $400,000. On May 6, 2024, Council approved a contingency increase of $771,000 for various activities related to final completion.
In order to ensure a fully operational facility, the UFES facility requires performance testing, which occurred in February 2025. During the testing, the UFES system received flow in excess of the tank capacity which overwhelmed the facility and resulted in flooding of the mechanical vault. APEC has been issued a Work Change Directive to proceed with repairing the damaged components of the mechanical vault and restore full functionality to the UFES facility. The total cost of this repair is estimated to be $522,000 and other potential changes including provision of a temporary odor control system, which are estimated to be $100,000. An increase to the contingency reserve is now requested because the remaining contingency balance of $62,879 is not sufficient to execute the anticipated change orders.
To mitigate risks associated with SSOs, and to provide flexibility for staff to negotiate contract change orders in a timely manner, staff recommends increasing the contingency reserve by an additional $600,000, for a revised total contingency in the amount of $6,271,000.
CITY OF SAN MATEO
BUDGET IMPACT:
Funding for this additional contingency amount is available within the Basins 2 & 3 Collection System Improvements (46s003) project budget.
ENVIRONMENTAL DETERMINATION:
The work addressed by this administrative report is being undertaken to support the Clean Water Program. This project is subject to the requirements of the California Environmental Quality Act (CEQA), the general components of which are included as part of the Final Programmatic Environmental Impact Report (Final PEIR) (SCH No. 201532006) that was prepared for the Clean Water Program. The Final PEIR was certified by City Council on June 6, 2016.
NOTICE PROVIDED
All meeting noticing requirements were met.
ATTACHMENTS
None
STAFF CONTACT
Tom Williams, Senior Engineer
[email protected]
(650) 522-7307